Microbial larvicide application by a large-scale, community-based program reduces malaria infection prevalence in urban Dar es Salaam, Tanzania.

<h4>Background</h4>Malaria control in Africa is most tractable in urban settlements yet most research has focused on rural settings. Elimination of malaria transmission from urban areas may require larval control strategies that complement adult mosquito control using insecticide-treated...

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Main Authors: Yvonne Geissbühler, Khadija Kannady, Prosper Pius Chaki, Basiliana Emidi, Nicodem James Govella, Valeliana Mayagaya, Michael Kiama, Deo Mtasiwa, Hassan Mshinda, Steven William Lindsay, Marcel Tanner, Ulrike Fillinger, Marcia Caldas de Castro, Gerry Francis Killeen
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2009-01-01
Series:PLoS ONE
Online Access:https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19333402/?tool=EBI
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author Yvonne Geissbühler
Khadija Kannady
Prosper Pius Chaki
Basiliana Emidi
Nicodem James Govella
Valeliana Mayagaya
Michael Kiama
Deo Mtasiwa
Hassan Mshinda
Steven William Lindsay
Marcel Tanner
Ulrike Fillinger
Marcia Caldas de Castro
Gerry Francis Killeen
author_facet Yvonne Geissbühler
Khadija Kannady
Prosper Pius Chaki
Basiliana Emidi
Nicodem James Govella
Valeliana Mayagaya
Michael Kiama
Deo Mtasiwa
Hassan Mshinda
Steven William Lindsay
Marcel Tanner
Ulrike Fillinger
Marcia Caldas de Castro
Gerry Francis Killeen
author_sort Yvonne Geissbühler
collection DOAJ
description <h4>Background</h4>Malaria control in Africa is most tractable in urban settlements yet most research has focused on rural settings. Elimination of malaria transmission from urban areas may require larval control strategies that complement adult mosquito control using insecticide-treated nets or houses, particularly where vectors feed outdoors.<h4>Methods and findings</h4>Microbial larvicide (Bacillus thuringiensis var. israelensis (Bti)) was applied weekly through programmatic, non-randomized community-based, but vertically managed, delivery systems in urban Dar es Salaam, Tanzania. Continuous, randomized cluster sampling of malaria infection prevalence and non-random programmatic surveillance of entomological inoculation rate (EIR) respectively constituted the primary and secondary outcomes surveyed within a population of approximately 612,000 residents in 15 fully urban wards covering 55 km(2). Bti application for one year in 3 of those wards (17 km(2) with 128,000 residents) reduced crude annual transmission estimates (Relative EIR [95% Confidence Interval] = 0.683 [0.491-0.952], P = 0.024) but program effectiveness peaked between July and September (Relative EIR [CI] = 0.354 [0.193 to 0.650], P = 0.001) when 45% (9/20) of directly observed transmission events occurred. Larviciding reduced malaria infection risk among children < or =5 years of age (OR [CI] = 0.284 [0.101 to 0.801], P = 0.017) and provided protection at least as good as personal use of an insecticide treated net (OR [CI] = 0.764 [0.614-0.951], P = 0.016).<h4>Conclusions</h4>In this context, larviciding reduced malaria prevalence and complemented existing protection provided by insecticide-treated nets. Larviciding may represent a useful option for integrated vector management in Africa, particularly in its rapidly growing urban centres.
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spelling doaj.art-a33c612644d941a38ae145a4189a6dc92022-12-21T21:32:57ZengPublic Library of Science (PLoS)PLoS ONE1932-62032009-01-0143e510710.1371/journal.pone.0005107Microbial larvicide application by a large-scale, community-based program reduces malaria infection prevalence in urban Dar es Salaam, Tanzania.Yvonne GeissbühlerKhadija KannadyProsper Pius ChakiBasiliana EmidiNicodem James GovellaValeliana MayagayaMichael KiamaDeo MtasiwaHassan MshindaSteven William LindsayMarcel TannerUlrike FillingerMarcia Caldas de CastroGerry Francis Killeen<h4>Background</h4>Malaria control in Africa is most tractable in urban settlements yet most research has focused on rural settings. Elimination of malaria transmission from urban areas may require larval control strategies that complement adult mosquito control using insecticide-treated nets or houses, particularly where vectors feed outdoors.<h4>Methods and findings</h4>Microbial larvicide (Bacillus thuringiensis var. israelensis (Bti)) was applied weekly through programmatic, non-randomized community-based, but vertically managed, delivery systems in urban Dar es Salaam, Tanzania. Continuous, randomized cluster sampling of malaria infection prevalence and non-random programmatic surveillance of entomological inoculation rate (EIR) respectively constituted the primary and secondary outcomes surveyed within a population of approximately 612,000 residents in 15 fully urban wards covering 55 km(2). Bti application for one year in 3 of those wards (17 km(2) with 128,000 residents) reduced crude annual transmission estimates (Relative EIR [95% Confidence Interval] = 0.683 [0.491-0.952], P = 0.024) but program effectiveness peaked between July and September (Relative EIR [CI] = 0.354 [0.193 to 0.650], P = 0.001) when 45% (9/20) of directly observed transmission events occurred. Larviciding reduced malaria infection risk among children < or =5 years of age (OR [CI] = 0.284 [0.101 to 0.801], P = 0.017) and provided protection at least as good as personal use of an insecticide treated net (OR [CI] = 0.764 [0.614-0.951], P = 0.016).<h4>Conclusions</h4>In this context, larviciding reduced malaria prevalence and complemented existing protection provided by insecticide-treated nets. Larviciding may represent a useful option for integrated vector management in Africa, particularly in its rapidly growing urban centres.https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19333402/?tool=EBI
spellingShingle Yvonne Geissbühler
Khadija Kannady
Prosper Pius Chaki
Basiliana Emidi
Nicodem James Govella
Valeliana Mayagaya
Michael Kiama
Deo Mtasiwa
Hassan Mshinda
Steven William Lindsay
Marcel Tanner
Ulrike Fillinger
Marcia Caldas de Castro
Gerry Francis Killeen
Microbial larvicide application by a large-scale, community-based program reduces malaria infection prevalence in urban Dar es Salaam, Tanzania.
PLoS ONE
title Microbial larvicide application by a large-scale, community-based program reduces malaria infection prevalence in urban Dar es Salaam, Tanzania.
title_full Microbial larvicide application by a large-scale, community-based program reduces malaria infection prevalence in urban Dar es Salaam, Tanzania.
title_fullStr Microbial larvicide application by a large-scale, community-based program reduces malaria infection prevalence in urban Dar es Salaam, Tanzania.
title_full_unstemmed Microbial larvicide application by a large-scale, community-based program reduces malaria infection prevalence in urban Dar es Salaam, Tanzania.
title_short Microbial larvicide application by a large-scale, community-based program reduces malaria infection prevalence in urban Dar es Salaam, Tanzania.
title_sort microbial larvicide application by a large scale community based program reduces malaria infection prevalence in urban dar es salaam tanzania
url https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/19333402/?tool=EBI
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